Studies performed during the past year on metastatic variant lines isolated by Fidler show increases of cell surface exposure of GM3 ganglioside and certain sialyl glycoproteins (with m.w. of 66,000 in vitro and 97,000, 84,000, 74,000, and 66,000 in vivo). The first objective of the study this year is to study composition and organization of cell surface glycoprotein and gangliosides of spontaneously metastasizing lung and lymph node clones of B16F1 and B16F10 melanoma and newly derived metastatic variant lines of SV-40 transformed 3T3 cells and relate such changes to the biological properties such as tumor growth and incidence of metastasis. The second objective is to study the display and levels of cell surface glycosyl transferase and glycosyl hydrolase using covalent glycolipid-glass complexes as substrates to evaluate their possible involvement in adhesive or invasive properties of several metastatic, and related, less metastatic tumor lines.